Recently, there have been researches on various liquid feeding mechanisms and methods where a filling container and ultrafine flow passages are formed on a piece of microchip, and a sample or a liquid specimen is fed and subjected to reaction under controlled conditions for a gene analysis, a blood examination or the like (patent literature 1).
In such an analysis or examination, it is crucial to prevent an artificial error such as the contamination of a sample or a specimen, an error in specimen injection or an error in an amount of test reagent. Particularly when a specimen is used in DNA identification or the like, reliability is required in injection of a specimen into an analyzer. To cope with such requirement, patent literature 2 discloses a specimen filling device for injecting a specimen into a microchip. The specimen filling device is mounted with a specimen package having a specimen chamber filled with a specimen, and when a projecting part formed on the specimen chamber is subjected to an external force, a portion of a bottom part is released, thereby discharging the specimen.
This specimen filling device is recognized as effective for preventing an artificial error such as contamination of a specimen, an error in specimen injection or an error in an amount of test reagent. However, the specimen filling device has the following drawback with respect to discharging of a specimen.
Specifically, when an external force is applied to the projecting part formed on a bottom part of the specimen chamber to break off the bottom part from a part to be broken around the projecting part, there is a possibility that the bottom part is deflected in the vicinity of the projecting part because the specimen chamber is formed of a material having resilience, thus only a portion of the part to be broken can break and other portions of the part remain unbroken, which means that a discharge port for discharging a specimen cannot be completely formed. Even when the discharge port could be completely formed, there still exists a possibility that a restoring force generated by resiliency acts to make the projecting part return to its original position and close the discharge port.
Further, in terms of ensuring a large discharge port, it is desirable to increase a height of the projecting part and deeply push the projecting part into the inside of the specimen chamber. In this case, however, at the time of inflating a film by compressed air to discharge a specimen to the outside as shown in FIG. 4(c) in patent literature 2, there exists a possibility that the inflation of the film is hindered by the projecting part pushed into the inside of the specimen chamber and the specimen cannot be sufficiently discharged to the outside.